Marked Increase in Spinal Deformity Surgery Throughout the United States

The Importance of Planning Ahead: A Three-Dimensional Analysis of the Novel Trans-Facet Corridor for Posterior Lumbar Interbody Fusion Using Segmentation Technology

BACKGROUND

The rise of minimally invasive lumbar fusions and advanced imaging technologies has facilitated the introduction of novel surgical techniques with the trans-facet approach being one of the newest additions. We aimed to quantify any pathology-driven anatomic changes to the trans-facet corridor, which could thereby alter the ideal laterality of approach to the disc space.

METHODS

In this retrospective cohort study, we measured the areas and maximum permissible cannula diameters of the trans-facet corridor using commercially available software (BrainLab, Munich, Germany). Exiting and traversing nerve roots, thecal sacs, and lumbar vertebrae were manually segmented on T2-SPACE magnetic resonance imaging. Spondylolisthesis, disc protrusions, and disc space heights were recorded.

RESULTS

A total of 118 trans-facet corridors were segmented bilaterally in 16 patients (65.6 ± 12.1 years, 43.8% female, body mass index 29.2 ± 5.1 kg/m2). The mean areas at L1-L2, L2-L3, L3-L4, and L4-L5 were 89.4 ± 24.9 mm2, 124 ± 39.4 mm2, 123 ± 26.6 mm2, and 159 ± 42.7 mm2, respectively. The mean permissible cannula diameter at the same levels were 7.85 ± 1.43 mm, 8.98 ± 1.72 mm, 8.93 ± 1.26 mm, and 10.2 ± 1.94 mm, respectively. Both parameters increased caudally. Higher degrees for spondylolisthesis were associated with larger areas and maximum cannula diameters on regression analysis (P < 0.001).

CONCLUSIONS

Our results illustrate that pathology, like spondylolisthesis, can increase the area of the trans-facet corridor. By understanding this effect, surgeons can better decide on the optimal approach to the disc while taking into consideration a patient's unique anatomy.

Adding Vertebral Bone Quality to the Fusion Risk Score: Does It Improve Predictions of Postoperative Complications?

STUDY DESIGN

Retrospective review of prospectively collected data.

OBJECTIVE

The current study evaluates whether the addition of the Vertebral Bone Quality (VBQ) score to the Fusion Risk Score (FRS) improves its ability to predict perioperative outcomes.

SUMMARY OF BACKGROUND DATA

The FRS was developed to assess preoperative risk in patients undergoing thoracic and lumbar fusions. It includes patient-derived and surgical variables, but it does not include one that directly accounts for bone health. The VBQ score allows assessment of bone quality and has been shown to correlate to DEXA-measured bone mineral density (BMD) scores.

METHODS

The VBQ score was weighted based on a regression model and then added to the FRS (FRS/VBQ). The ability of the two scores to predict the outcomes was then assessed using the area under the curve (AUC).

PATIENT SAMPLE

Patients undergoing elective thoracic and lumbar spinal fusion from January 2019 to June 2020 were included.

OUTCOME MEASURES

The study evaluated various perioperative adverse outcomes, including major and minor adverse events, discharge other than home, extended length of stay, 90-day emergency department visits, 90-day readmission, and 90-day and 2-year reoperation rates.

RESULTS

A total of 353 met the inclusion and exclusion criteria. The FRS/VBQ demonstrated improved predictive ability compared with the FRS alone when evaluating 90-day reoperation. Both scores showed fair predictive ability for any adverse event, major adverse events, minor adverse events, and 2-year reoperation rates, with AUCs ranging from 0.700 to 0.737. Both had poor predictive ability for the other outcomes.

CONCLUSIONS

Adding VBQ to the FRS significantly enhances its predictive accuracy for reoperation rate. This updated risk score provides a more comprehensive understanding of a patient's preoperative risk profile, aiding both patients and physicians in assessing surgical risks and optimizing outcomes through preoperative risk stratification.

LEVEL OF EVIDENCE

3.

American College of Surgeons National Surgical Quality Improvement Program Surgical Risk Calculator as a Predictor of Postoperative Outcomes After Adult Spinal Deformity Surgery: A Retrospective Cohort Analysis

BACKGROUND AND OBJECTIVES

In recent years, there has been an outpouring of scoring systems that were built to predict outcomes after various surgical procedures; however, research validating these studies in spinal surgery is quite limited. In this study, we evaluated the predictability of the American College of Surgeons National Surgical Quality Improvement Program Surgical Risk Calculator (ACS NSQIP SRC) for various postoperative outcomes after spinal deformity surgery.

METHODS

A retrospective chart review was conducted to identify patients who underwent spinal deformity surgery at our hospital between January 1, 2014, and December 31, 2022. Demographic and clinical data necessary to use the ACS NSQIP SRC and postoperative outcomes were collected for these patients. Predictability was analyzed using the area under the curve (AUC) of receiver operating characteristic curves and Brier scores.

RESULTS

Among the 159 study patients, the mean age was 64.5 ± 9.5 years, mean body mass index was 31.9 ± 6.6, and 95 (59.7%) patients were women. The outcome most accurately predicted by the ACS NSQIP SRC was postoperative pneumonia (observed = 5.0% vs predicted = 3.2%, AUC = 0.75, Brier score = 0.05), but its predictability still fell below the acceptable threshold. Other outcomes that were underpredicted by the ACS NSQIP SRC were readmission within 30 days (observed = 13.8% vs predicted = 9.0%, AUC = 0.63, Brier score = 0.12), rate of discharge to nursing home or rehabilitation facilities (observed = 56.0% vs predicted = 46.6%, AUC = 0.59, Brier = 0.26), reoperation (observed 11.9% vs predicted 5.4%, AUC = 0.60, Brier = 0.11), surgical site infection (observed 9.4% vs predicted 3.5%, AUC = 0.61, Brier = 0.05), and any complication (observed 33.3% vs 19%, AUC = 0.65, Brier = 0.23). Predicted and observed length of stay were not significantly associated (β = 0.132, P = .47).

CONCLUSION

The ACS NSQIP SRC is a poor predictor of outcomes after spinal deformity surgery.

What Is the Carbon Footprint of Adult Spinal Deformity Surgery?

Background/Objectives: While the economic cost of adult spinal deformity (ASD) surgery has been studied extensively, its environmental impact is unknown. The aim of this study is to determine the carbon footprint (CF) associated with ASD surgery. Methods: ASD patients who underwent > four levels of corrective surgery between 2017 and 2021 were included. The open group included a posterior-only, single-stage technique, while the minimally invasive surgery (MIS) group was defined as the use of lateral interbody fusion and percutaneous posterior screw fixation. The two groups were propensity-score matched to adjust for baseline demographic, surgical, and radiographic characteristics. Data on all disposables and reusable instruments, anesthetic gas, and non-gas medications used during surgery were collected from medical records. The CF of transporting, using, and disposing of each product and the footprint of energy use in operating rooms were calculated. The CF produced was evaluated using the carbon dioxide equivalent (CO2e), which is relative to the amount of CO2 with an equivalent global warming potential. Results: Of the 175 eligible patients, 15 pairs (65 ± 9 years, 47% female) were properly matched and analyzed for all variables. The average CF generated per case was 147.7 ± 37.3 kg-CO2e, of which 54% was attributable to energy used to sterilize reusable instruments, followed by anesthetic gas released into the environment (17%) and operating room air conditioning (15%). Conclusions: The CF generated during ASD surgery should be reduced using a multidisciplinary approach, taking into account that different surgical procedures have different impacts on carbon emission sources.

Characterizing Negative Online Reviews of Spine Surgeons

DESIGN

Retrospective review.

OBJECTIVE

Characterize negative reviews of spine surgeons in the United States.

SUMMARY

Physician rating websites significantly influence the selection of doctors by other patients. Negative experiences are impacted by various factors, both clinical and nonclinical, geography, and practice structure. The purpose of this study was to evaluate and categorize negative reviews of spine surgeons in the United States, with a focus on surgical versus nonsurgical reviewers.

METHODS

Spine surgeons were selected from available online professional society membership directories. A search for reviews was performed on Healthgrades.com, Vitals.com, and RateMDs.com for the past 10 years. Free response reviews were coded by complaint, and qualitative analysis was performed. χ 2 and Fisher exact tests were used to compare categorical variables, and multiple comparisons were adjusted with Benjamini-Hochberg correction. A binary logistic regression model was performed for the top three most mentioned nonclinical and clinical complaint labels. A P -value <0.05 was considered statistically significant.

RESULTS

A total of 16,695 online reviews were evaluated, including 1690 one-star reviews (10.1%). Among one-star reviews, 64.7% were written by nonsurgical patients and 35.3% by surgical patients. Nonclinical and clinical comments constituted 54.9% and 45.1% of reviews, respectively. Surgeons in the South had more "bedside manner" comments (43.3%, P <0.0001), while Northeast surgeons had more "poor surgical outcome" remarks compared with all other geographic regions (14.4%, P <0.001). Practicing in the South and Northeast were independent predictors of having complaints about "bedside manner" and "poor surgical outcome," respectively.

CONCLUSION

Most one-star reviews of spine surgeons were attributed to nonsurgical patients, who tended to be unsatisfied with nonclinical factors, especially "bedside manner." However, there was substantial geographic variation. These results suggest that spine surgeons could benefit from focusing on nonclinical factors (bedside manner), especially among nonoperative patients, and that regional nuances should be considered in delivering spine care.

LEVEL OF EVIDENCE

Level- 5.

Single Surgeon Comparison of Midline Versus Overlapping Locoregional Flap Closure Following Spinal Instrumentation

BACKGROUND

Two techniques for paraspinous muscle flap closure of spine surgeries have been described: one with tension-free mobilization of the muscle flaps approximated at the midline and one with perforators more aggressively dissected to allow for overlapping of the flaps. We seek to compare the surgical outcomes in patients who underwent either type of complex spinal closure as no investigation has yet evaluated a superior technique.

METHODS

An institutional review board (IRB)-approved retrospective analysis was conducted on all patients who underwent spine surgery followed by locoregional muscle flap complex closure performed by a single plastic surgeon between January 2016 and July 2021. Patients were divided into 2 groups based on which closure method was employed. Odds ratios (ORs) and 95% confidence intervals (CIs) were computed by multivariable logistic regression with Firth's correction.

RESULTS

One hundred and 10 patients with similar baseline demographics were included. There were significantly more smokers (15% vs. 0%, P = 0.02) and a significantly greater rate of postoperative radiation (40% vs. 17%, P = 0.009) in the overlapping group. After controlling for smoking and postoperative radiation, the incidence of surgical site infection, skin necrosis, dehiscence, hematoma, and seroma did not differ between the groups. The procedure length per centimeter of closure was shorter in the midline approximation group, although this data fell just short of significance (3.2 vs. 3.8 minutes/cm, P = 0.08).

CONCLUSIONS

The present study demonstrates that both the overlapping and midline approximation of muscle flaps are equally safe and effective strategies for locoregional closure of spinal wounds.

Preoperative nutritional optimization for adult spinal deformity: Review

PURPOSE

The main objective of this review article is to examine the role that nutrition has on adult spinal deformity. The information presented in this review aims to provide spine surgeons with a broad overview of screening, assessment, and interventional strategies that may be used for presurgical nutritional optimization.

METHODS

A comprehensive literature review utilizing three biomedical databases was performed to generate articles of interest. Published articles related to nutrition, adult spinal deformity, spine surgery and orthopaedics were reviewed for the composition of this article. Nutrition may play a role in optimizing postoperative outcomes following adult spinal deformity surgeries, such as limiting delirium, length of stay, blood transfusion, and other medical complications. The use of screening tools, such as the PNI and CONUT score can assess preoperative nutritional status and may provide some utility in evaluating nutrition status in patients undergoing deformity surgery. Balancing both macronutrients and micronutrients, notably, carbohydrates, protein, albumin, and vitamin D can play a role in preoperative optimization.

CONCLUSION

Adult spinal deformity patients are at an increased risk for malnutrition. These patients should be assessed for nutrition status to prime them for surgery, minimize complications, and maximize their outcomes. However, further studies are needed to determine how nutrition ultimately affects adult spinal deformity patients in the postoperative period and to establish specific nutritional recommendations for this unique population.

Incidence and Risk Factors of the Caudal Screw Loosening after Pelvic Fixation for Adult Spinal Deformity: A Systematic Review and Meta-analysis

The purpose of this study was to assess the factors affecting caudal screw loosening after spinopelvic fixation for adult patients with spinal deformity. This meta-analysis calculated the weighted mean difference (WMD) and odds ratio (OR) using Review Manager ver. 5.3 (RevMan; Cochrane, London, UK). The loosening group was older than the control group (WMD, 2.17; 95% confidence interval [CI], 0.48-3.87; p=0.01). The S2 alar-iliac (S2AI) could prevent the caudal screw from loosening (OR, 0.43; 95% CI, 0.20-0.94; p=0.03). However, gender distribution (p=0.36), the number of fusion segments (p=0.24), rod breakage (p=0.97), T-score (p=0.10), and proximal junctional kyphosis (p=0.75) demonstrated no difference. Preoperatively, only pelvic incidence (PI) in the loosening group was higher (WMD, 5.08; 95% CI, 2.71-7.45; p<0.01), while thoracic kyphosis (p=0.09), lumbar lordosis (LL) (p=0.69), pelvic tilt (PT) (p=0.31), pelvic incidence minus lumbar lordosis (PI-LL) (p=0.35), sagittal vertical axis (SVA) (p=0.27), and T1 pelvic angle (TPA) demonstrated no difference (p=0.10). PI-LL (WMD, 6.05; 95% CI, 0.96-11.14; p=0.02), PT (WMD, 4.12; 95% CI, 0.99-7.26; p=0.01), TPA (WMD, 4.72; 95% CI, 2.35-7.09; p<0.01), and SVA (WMD, 13.35; 95% CI, 2.83-3.87; p=0.001) were higher in the screw loosening group immediately postoperatively. However, TK (p=0.24) and LL (p=0.44) demonstrated no difference. TPA (WMD, 8.38; 95% CI, 3.30-13.47; p<0.01), PT (WMD, 6.01; 95% CI, 1.47-10.55; p=0.01), and SVA (WMD, 23.13; 95% CI, 12.06-34.21; p<0.01) were higher in the screw loosening group at the final follow-up. However, PI-LL (p=0.17) demonstrated no significant difference. Elderly individuals were more susceptible to the caudal screw loosening, and the S2AI screw might better reduce the caudal screw loosening rate than the iliac screws. The lumbar lordosis and sagittal alignment should be reconstructed properly to prevent the caudal screw from loosening. Measures to block sagittal alignment deterioration could also prevent the caudal screw from loosening.

Effectiveness of a two-stage posterior-anterior-posterior surgery using subcutaneously preserved autologous bone grafts for adult spinal deformity: a retrospective observational study

BACKGROUND

To achieve optimal correction of rigid kyphoscoliosis, we developed a novel two-stage posterior-anterior-posterior (PAP) surgery using subcutaneously preserved autologous bone grafts. This study aimed to investigate the effectiveness of two-stage PAP surgery versus single-stage anterior-posterior (AP) surgery.

METHODS

This was a retrospective analysis of patients undergoing combined anterior-posterior long-level fusion for adult spinal deformity (ASD) with a minimum 2-year follow-up. The indications for two-stage PAP surgery were rigid thoracolumbar deformity associated with hypertrophic facet arthritis and/or a large pelvic incidence-lumbar lordosis mismatch of > 25°. In the first stage of PAP surgery, pedicle screw insertion and multilevel Ponte osteotomies were performed. The resected local bone was embedded under sutured fascia. One week later, the embedded bone was retrieved in the right lateral position and used as an autograft for lateral lumbar interbody fusion. Final deformity correction was performed in the prone position.

RESULTS

From January 2018 to April 2021, 12 and 16 patients with ASD underwent two-stage PAP surgery (PAP group) and single-stage AP surgery (AP group), respectively. Although PAP surgery was associated with a significantly longer operation time, the total blood loss volume was significantly less in the PAP group than the AP group. Compared with the AP group, the PAP group showed significantly larger postoperative changes in radiological parameters in the sagittal and coronal planes. The overall complication rate did not differ significantly between the two groups.

CONCLUSION

Two-stage PAP surgery provided effective correction of rigid kyphoscoliosis without increasing blood loss and postoperative complication rates.

Optimizing Preoperative Chronic Pain Management in Elective Spine Surgery Patients: A Narrative Review of Outcomes with Opioid and Adjuvant Pain Therapies

» Chronic preoperative opioid use negatively affects outcomes after spine surgery, with increased complications and reoperations, longer hospital stays, decreased return-to-work rates, worse patient-reported outcomes, and a higher risk of continued opioid use postoperatively.» The definition of chronic opioid use is not consistent across studies, and a more specific and consistent definition will aid in stratifying patients and understanding their risk of inferior outcomes.» Preoperative weaning periods and maximum dose thresholds are being established, which may increase the likelihood of achieving a meaningful improvement after surgery, although higher level evidence studies are needed.» Spinal cord stimulators and intrathecal drug delivery devices are increasingly used to manage chronic back pain and are equivalent or perhaps even superior to opioid treatment, although few studies exist examining how patients with these devices do after subsequent spine surgery.» Further investigation is needed to determine whether a true mechanistic explanation exists for spine-related analgesia related to spinal cord stimulators and intrathecal drug delivery devices.

Impact of frailty on the outcomes of patients undergoing degenerative spine surgery: a systematic review and meta-analysis

BACKGROUND

Degenerative spinal diseases are common in older adults with concurrent frailty. Preoperative frailty is a strong predictor of adverse clinical outcomes after surgery. This study aimed to investigate the association between health-related outcomes and frailty in patients undergoing spine surgery for degenerative spine diseases.

METHODS

A systematic review and meta-analysis were performed by electronically searching Ovid-MEDLINE, Ovid-Embase, Cochrane Library, and CINAHL for eligible studies until July 16, 2022. We reviewed all studies, excluding spinal tumours, non-surgical procedures, and experimental studies that examined the association between preoperative frailty and related outcomes after spine surgery. A total of 1,075 articles were identified in the initial search and were reviewed by two reviewers, independently. Data were subjected to qualitative and quantitative syntheses by meta-analytic methods.

RESULTS

Thirty-eight articles on 474,651 patients who underwent degenerative spine surgeries were included and 17 papers were quantitatively synthesized. The health-related outcomes were divided into clinical outcomes and patient-reported outcomes; clinical outcomes were further divided into postoperative complications and supportive management procedures. Compared to the non-frail group, the frail group was significantly associated with a greater risk of high mortality, major complications, acute renal failure, myocardial infarction, non-home discharge, reintubation, and longer length of hospital stay. Regarding patient-reported outcomes, changes in scores between the preoperative and postoperative Oswestry Disability Index scores were not associated with preoperative frailty.

CONCLUSIONS

In degenerative spinal diseases, frailty is a strong predictor of adverse clinical outcomes after spine surgery. The relationship between preoperative frailty and patient-reported outcomes is still inconclusive. Further research is needed to consolidate the evidence from patient-reported outcomes.

A novel method for assigning bone material properties to a comprehensive patient-specific pelvic finite element model using biplanar multi-energy radiographs

The increasing prevalence of adult spinal deformity requires long spino-pelvic instrumentation, but pelvic fixation faces challenges due to distal forces and reduced bone quality. Bi-planar multi-energy X-rays (BMEX) were used to develop a patient-specific finite element model (FEM) for evaluating pelvic fixation. Calibration involved 10 patients, and an 81-year-old female test case was used for FEM customization and pullout simulation validation. Calibration yielded a root mean square error of 74.7 mg/cm3 for HU. The simulation accurately replicated the experimental pullout test with a force of 565 N, highlighting the method's potential for optimizing biomechanical performance for pelvic fixation.

Plastic Surgery Closure of Complex Spinal Wounds

Wound breakdown and infection are common complications after complex spine surgery and may occur in up to 40% of high-risk patients. These are challenging scenarios which can result in a prolonged hospital stay, revision surgery, and elevated costs. Reconstructive specialists can do prophylactic closures for high-risk groups to potentially reduce the risk of developing a wound complication. These plastic surgery techniques often involve multilayered closure, with the addition of local muscle and/or fasciocutaneous flaps. The goal of this study was to review the literature for risks associated with wound complications, identification of high-risk patients, and the advantages of using plastic surgery techniques. In addition, we elaborate on the multilayered and flap closure technique for complex spine surgery which is done at our institution.

Awake Spinal Fusion Is Associated with Reduced Length of Stay, Opioid Use, and Time to Ambulation Compared to General Anesthesia: A Matched Cohort Study

OBJECTIVE

There is increasing interest in performing awake spinal fusion under spinal anesthesia (SA). Evidence supporting SA has been positive, albeit limited. The authors set out to investigate the effects of SA versus general anesthesia (GA) for spinal fusion procedures on length of stay (LOS), opioid use, time to ambulation (TTA), and procedure duration.

METHODS

The authors performed a retrospective review of a single surgeon's patients who underwent lumbar fusions under SA versus GA from June of 2020 to June of 2022. SA patients were compared to demographically matched GA counterparts undergoing comparable procedures. Analyzed outcomes include operative time, opioid usage in morphine milligram equivalents, TTA, and LOS.

RESULTS

Ten SA patients were matched to 10 GA counterparts. The cohort had a mean age of 66.77, a mean body mass index of 27.73 kg/m2, and a median American Society of Anesthesiologists Physical Status Score of 3.00. LOS was lower in SA versus GA patients (12.87 vs. 50.79 hours, P = 0.001). Opioid utilization was reduced in SA versus GA patients (10.76 vs. 31.43 morphine milligram equivalents, P = 0.006). TTA was reduced in SA versus GA patients (7.22 vs. 29.87 hours, P = 0.022). Procedure duration was not significantly reduced in SA patients compared to GA patients (139.3 vs. 188.2 minutes, P = 0.089).

CONCLUSIONS

These preliminary retrospective results suggest the use of SA rather than GA for lumbar fusions is associated with reduced hospital LOS, reduced opioid utilization, and reduced TTA. Future randomized prospective studies are warranted to determine if SA usage truly leads to these beneficial outcomes.

Short-Segment versus Long-Segment Spinal Fusion Constructs for the Treatment of Adult Degenerative Scoliosis: A Comparison of Clinical Outcomes

OBJECTIVE

To compare clinical outcomes of patients diagnosed with degenerative scoliosis undergoing short-segment versus long-segment spinal fusion.

METHODS

A retrospective cohort study was conducted of patients with degenerative thoracolumbar scoliosis undergoing elective spinal fusion at a single academic medical center. Cohorts were divided into short-segment (<3) or long-segment (≥3) groups.

RESULTS

A total of 197 patients (122 short, 75 long) were included. Patients undergoing short-segment fusion more frequently presented with radiculopathy (P < 0.001) and had greater baseline visual analog scale (VAS) leg scores (P < 0.001). Patients with long-segment fusions had longer hospital length of stay (short, 3.82 ± 2.98 vs. long, 7.40 ± 6.85 days; P < 0.001), lower home discharge rates (short, 80.3% vs. long, 51.8; P = 0.003), higher revision surgery rates (short, 10.77% vs. long, 25.3%; P = 0.012), and greater percentage curve correction (short, 37.3% ± 25.9% vs. long, 45.1% ± 23.9%; P = 0.048). No significant differences were noted in postoperative complication rates (short, 1.64% vs. long, 5.33%; P = 0.143). At 1 year, patients with long fusions had worse ΔOswestry Disability Index (ODI) (P = 0.024), ΔVAS leg score (P = 0.002), and VAS leg minimum clinically important difference % (P = 0.003). Multivariate regression found that short-segment fusions were associated with greater improvements in ODI (P = 0.029), Physical Component Summary-12 (P = 0.024), and VAS leg score at 1 year (P = 0.002).

CONCLUSIONS

Patients undergoing short-segment fusions more frequently presented with radiculopathy and had higher preoperative VAS leg scores compared with those receiving long constructs. Short-construct fusions in appropriately selected patients may provide satisfactory improvements in patient-reported outcome measures, particularly ΔODI and ΔVAS leg score, and mitigate hospital length of stay, revision surgery rates, and nonhome discharge.

Disparities in Elective Spine Surgery for Medicaid Beneficiaries: A Systematic Review

STUDY DESIGN

Systematic review.

OBJECTIVES

We sought to synthesize the literature investigating the disparities that Medicaid patients sustain with regards to 2 types of elective spine surgery, lumbar fusion (LF) and anterior cervical discectomy and fusion (ACDF).

METHODS

Our review was constructed in accordance with Preferred Reporting Items and Meta-analyses (PRISMA) guidelines and protocol. We systematically searched PubMed, Embase, Scopus, CINAHL, and Web of Science databases. We included studies comparing Medicaid beneficiaries to other payer categories with regards to rates of LF and ACDF, costs/reimbursement, and health outcomes.

RESULTS

A total of 573 articles were assessed. Twenty-five articles were included in the analysis. We found that the literature is consistent with regards to Medicaid disparities. Medicaid was strongly associated with decreased access to LF and ACDF, lower reimbursement rates, and worse health outcomes (such as higher rates of readmission and emergency department utilization) compared to other insurance categories.

CONCLUSIONS

In adult patients undergoing elective spine surgery, Medicaid insurance is associated with wide disparities with regards to access to care and health outcomes. Efforts should focus on identifying causes and interventions for such disparities in this vulnerable population.

The relationship between spinal alignment and activity of paravertebral muscle during gait in patients with adult spinal deformity: a retrospective study

BACKGROUND

Spinal alignment in patients with adult spinal deformity (ASD) changes between rest and during gait. However, it remains unclear at which point the compensated walking posture breaks down and how muscles respond. This study used time-synchronized electromyography (EMG) to investigate the relationship between dynamic spinal alignment and muscle activity during maximum walking duration to reveal compensation mechanisms.

METHODS

This study collected preoperative three-dimensional gait analysis data from patients who were candidates for corrective surgery for ASD from April 2015 to May 2019. We preoperatively obtained dynamic spinal alignment parameters from initiation to cessation of gait using a motion capture system with time-synchronized surface integrated EMG (iEMG). We compared chronological changes in dynamic spinal alignment parameters and iEMG values 1) immediately after gait initiation (first trial), 2) half of the distance walked (half trial), and 3) immediately before cessation (last trial).

RESULTS

This study included 26 patients (22 women, four men) with ASD. Spinal sagittal vertical axis distance during gait (SpSVA) increased over time (first vs. half vs. last, 172.4 ± 74.8 mm vs. 179.9 ± 76.8 mm vs. 201.6 ± 83.1 mm; P < 0.001). Cervical paravertebral muscle (PVM) and gluteus maximus activity significantly increased (P < 0.01), but thoracic and lumbar PVM activity did not change. Dynamic spinal alignment showed significant correlation with all muscle activity (cervical PVM, r = 0.41-0.54; thoracic PVM, r = 0.49-0.66; gluteus maximus, r = 0.54-0.69; quadriceps, r = 0.46-0.55) except lumbar PVM activity.

CONCLUSION

Spinal balance exacerbation occurred continuously in patients with ASD over maximum walking distance and not at specific points. To maintain horizontal gaze, cervical PVM and gluteus maximus were activated to compensate for a dynamic spinal alignment change. All muscle activities, except lumbar PVM, increased to compensate for the spinal malalignment over time.

Dysfunctional paraspinal muscles in adult spinal deformity patients lead to increased spinal loading

Purpose

Decreased spinal extensor muscle strength in adult spinal deformity (ASD) patients is well-known but poorly understood; thus, this study aimed to investigate the biomechanical and histopathological properties of paraspinal muscles from ASD patients and predict the effect of altered biomechanical properties on spine loading.

Methods

68 muscle biopsies were collected from nine ASD patients at L4–L5 (bilateral multifidus and longissimus sampled). The biopsies were tested for muscle fiber and fiber bundle biomechanical properties and histopathology. The small sample size (due to COVID-19) precluded formal statistical analysis, but the properties were compared to literature data. Changes in spinal loading due to the measured properties were predicted by a lumbar spine musculoskeletal model.

Results

Single fiber passive elastic moduli were similar to literature values, but in contrast, the fiber bundle moduli exhibited a wide range beyond literature values, with 22% of 171 fiber bundles exhibiting very high elastic moduli, up to 20 times greater. Active contractile specific force was consistently less than literature, with notably 24% of samples exhibiting no contractile ability. Histological analysis of 28 biopsies revealed frequent fibro-fatty replacement with a range of muscle fiber abnormalities. Biomechanical modelling predicted that high muscle stiffness could increase the compressive loads in the spine by over 500%, particularly in flexed postures.

Discussion

The histopathological observations suggest diverse mechanisms of potential functional impairment. The large variations observed in muscle biomechanical properties can have a dramatic influence on spinal forces. These early findings highlight the potential key role of the paraspinal muscle in ASD.

Patient Out-of-Pocket Cost Burden With Elective Orthopaedic Surgery

INTRODUCTION

Out-of-pocket (OOP) costs for medical and surgical care can result in substantial financial burden for patients and families. Relatively little is known regarding OOP costs for commercially insured patients receiving orthopaedic surgery. The aim of this study is to analyze the trends in OOP costs for common, elective orthopaedic surgeries performed in the hospital inpatient setting.

METHODS

This study used an employer-sponsored insurance claims database to analyze billing data of commercially insured patients who underwent elective orthopaedic surgery between 2014 and 2019. Patients who received single-level anterior cervical diskectomy and fusion (ACDF), single-level posterior lumbar fusion (PLF), total knee arthroplasty (TKA), and total hip arthroplasty (THA) were identified. OOP costs associated with the surgical episode were calculated as the sum of deductible payments, copayments, and coinsurance. Monetary data were adjusted to 2019 dollars. General linear regression, Wilcoxon-Mann-Whitney, and Kruskal-Wallis tests were used for analysis, as appropriate.

RESULTS

In total, 10,225 ACDF, 28,841 PLF, 70,815 THA, and 108,940 TKA patients were analyzed. Most patients in our study sample had preferred provider organization insurance plans (ACDF 70.3%, PLF 66.9%, THA 66.2%, and TKA 67.0%). The mean OOP costs for patients, by procedure, were as follows: ACDF $3,180 (SD = 2,495), PLF $3,166 (SD = 2,529), THA $2,884 (SD = 2,100), and TKA $2,733 (SD = 1,994). Total OOP costs increased significantly from 2014 to 2019 for all procedures (P < 0.0001). Among the insurance plans examined, patients with high-deductible health plans had the highest episodic OOP costs. The ratio of patient contribution (OOP costs) to total insurer contribution (payments from insurers to providers) was 0.07 for ACDF, 0.04 for PLF, 0.07 for THA, and 0.07 for TKA.

CONCLUSION

Among commercially insured patients who underwent elective spinal fusion and major lower extremity joint arthroplasty surgery, OOP costs increased from 2014 to 2019. The OOP costs for elective orthopaedic surgery represent a substantial and increasing financial burden for patients.

Is there an indication for surgery in patients with spinal deformities? - A critical appraisal

Background

High-quality evidence exists to support physiotherapy and brace treatment for scoliosis and other spinal deformities. However, according to previous systematic reviews, it seems that no evidence exists for surgery. Nevertheless, the number of research articles focussing on spinal surgery highly exceeds the number of articles focussing on conservative treatment.

Objective

The purpose of this study is to conduct an updated search for systematic reviews providing high-quality evidence for spinal surgery in patients with spinal deformities.

Method

A narrative review including PubMed and the Cochrane database was conducted on April 12, 2020, with the following search terms: (1) spinal deformities, surgery, systematic review and outcome; (2) kyphosis, surgery, systematic review and outcome; (3) Scheuermann's disease, surgery, systematic review and outcome, and (4) scoliosis, surgery, systematic review and outcome.

Results

No reviews containing prospective controlled or randomised controlled studies were found providing evidence for surgery.

Conclusions

A general indication for spine surgery just based on the Cobb angle is not given. In view of the long-term unknown variables and the possible long-term complications of such treatment, a surgical indication for patients with spinal deformities must be reviewed on an individual basis and considered carefully. A current systematic review appears necessary in order to be able to draw final conclusions on the indication for surgery in patients with spinal deformities.

Clinical implications

In view of the increasing number of surgeons with an affiliation to industry, the indication for surgery needs to be given by independent conservative specialists for spinal deformities in order to provide an objective recommendation.